Stamping machine



Oct. 24, 1950 -c. G. PETE RSON 2,527,448

' STAMPING MACHINE Filed July 5, 1945 3 Sheets$heet 1 as 7s I 1:] 5 68 Q Q g 6.9 952 70 HVVENTOR. 6224,

Oct. 24, 1950 Q PETERSON 2,527,448

STAMPING MACHINE Filed July 3, 1945 3 Sheets-Sheet 2 IN VEN TOR.

Oct. 24, 1950 2,527,448

C. G. PETERSON STAMPING MACHINE Filed July 3, 1945 3 Sheets-Sheet 3 INVENTOR.

Patented Oct. 24, 1950 UNITED STATES PATENT OFFICE 7 2,527,448 STAMPING MACHINE Carl GQPcterson, Cranston, R. I. Application July 3, 1945, Serial No. 602,968

. 3 Claims. 1

The present invention relates to stamping machines, and has particular reference to a novel construction for a punch press.

The principal object of the invention is to provide a punch press which utilizes an eccentric operating mechanism.

Another object of the invention is to provide a punch press which may be set for a desired fixed stroke, and which may be accurately adjusted for micrometer punch position changes during operation.

A further object of the invention is to utilize spaced bearings for the punch mechanism which maintain the desired punch alignment and minimize bearing wear.

An additional object is to provide a compact, light Weight punch press which is exceptionally rugged and accurate.

With the above and other objects and advantageous features in view, the invention consists of a novel arrangement of parts, more fully disclosed in the detaileddescription following, of a preferred constructional embodiment of the invention, which is illustrated in the accompanying drawings.

In the drawings:

Fig. 1 is a front elevation of a punch press embodying the invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a rear elevation thereof;

Fig. 4 is an enlarged perspective view showing the stroke setting elements;

Fig. 5 is an'enlarged perspective view, partly broken away; of the micrometer punch position adjusting parts; and

Fig. 6 is a detail plan showing the hand wheel for shifting the motor to take up belt slack and to change the speed ratio.

It has been found desirable to provide a compact, light weight punch press for continuous punching or stamping, which is exceptionally rugged and accurate,. and which may be set for a desired stroke and adjusted as to vertical punch position without stopping the punching operation to compensate for slightvariations in stock thickness, or to make slight changes in the punching or stamping impression. To this end, I provide a punch mechanism which is operated from an eccentric, and which is rigidly guided in spaced bearings, the punch mechanism being positive in action and settable for a desired stroke, andbeing adjustable during operation to obtain a desired micrometer punch position calibration.

Referring to the drawingsythe punch press are secured, the standards being in inverted V form and having a horizontal bearing [2 at the apex of the standards in which the drive shaft I3 is seated. An electric motor l4, having the usual electrical connections, is slidably mounted on transverse support rods I5, which are secured at their ends in spaced brackets l6, H, the brackets being bolted to U-shaped supporting straps !8, I9 mounted on the standards H. The motor shaft 20, see Fig. 2, has a stub extension 2| on which a spring pulley 22, of the change speed type, is keyed, a belt 23 connecting the pulley 22 to a second pulley 24 on a cross shaft 25 journaled in the bracket I6. A hand Wheel 26, see Fig. 3 and Fig. 6, may be used to turn a rod 21, threaded into the base 28 of the motor I4 to provide a lateral shift of the motor for taking up slack of the belt 23 andfor changing the speed ratio by varying the effective diameter of the pulley 22.

A power pulley 29 is keyed to the other end of the cross shaft 25 for. driving a chain belt 30 which in turn drives a fly wheel 3|, keyed to the drive shaft l3, when the clutch 32 is engaged. The drive shaft l3 has a block 33 mounted thereon, see Fig. 3, which has a stub shaft 34 on which an eccentric 35 is mounted, to operate a push rod 36 for intermittently periodically operating an adjustable stock feed device of the type shown in my prior Patent No. 2,317,481,which accurately imparts a step by step rotation to a shaft 31 for operating the stock feed device 38, which feed device includes a housing 39, a lower roll, and a spring pressedupper roll 4|, the two rolls 4!) and 4! having meshing end gears 42 and 43.

Referring now to Fig. 4, the drive shaft I3 has a cylindrical end 44 of larger diameter, which is recessed as indicated at 45 to receive a stroke control block 46 of fixed length, the block 46 being secured to the shaft end 44 by means of screws 41. The end 44 has an undercut slotted channel 48 which is a continuation of the recess 45, and slidably receives a block 49 on which an eccentric pin 50 is mounted, the block 49 being secured to the block 46 by means of a threaded through bolt 5|. When the block 49 is inserted in the channel 48 and the block 46 is secured to the shaft end 44, a closure ring 52 is mounted over the shaft end 44 and the bolt 5| is then inserted through an opening 53 in the ring 52 and threaded into the block 49 to lock the parts together.

. The block 46 is preferably one of a series of is mounted on-a base l0, on which standardsll 55. blocks of different length, for the purpose of shifting the eccentric pin a predetermined distance to the opposite side of the center of the drive shaft, the parts being so arranged that the power for punching or stamping is transmitted through the drive shaft and the block 46 directly to the block 49 of the eccentric pin. The ring 52 extends over the end of the recess 45, and the outer end of the block 46 is rounded to conform to and abut against the ring 52, whereby a rigid abutment is provided during the punching or stamping operation to take the thrust off the retaining screws 47.

A plate 54 having a cylindrical extension 55 is then seated over the eccentric pin 50 and a hollow slide block 56 is mounted over the plate 54, the cylindrical extension 55 seating in a receiving opening in the forward face plate 58 of the slide block 56 and the threaded end 59 of the eccentric pin 59 extending outwardly from the opening 51 to receive a washer 69 and a lock nut 6|. When the parts are assembled the plate 54 seats on the drive shaft end and the parts become locked together to form a rigid, substantially integral unit capable of transmitting very heavy power thrusts.

The slide block 56 has upper and lower fiat faces 62, 63 stepped below the upper and lower edges of the slide block face plate 58 to provide two parallel slide surfaces which are received between two cross bars 64, 65, see Fig. 1, secured to two upright rods 66, 61 by means of recessed portions, the rods being guided within two aligned split bearing seats 68, 69 of a vertical bearing support 10 integral with the standards II.

The rods 66, 61 are threaded at'their lower ends, and a cross bar 1| is threadedly mounted on the lower ends of the rods 66, 61 and carries a punch support 12 centrally thereof, a punch 13 being removably positioned in the punch support, and a spring pressed grip finger 54 also being mounted in the punch support. The stock fed forwardly by the feed device 38 passes over a bed plate 15 removably secured to the base It].

The upper ends of the threaded rods 66, El have worm gears 16, 11 keyed thereto and held in place by washers i8, 19 and end nuts 8|, 82, a cross shaft 83 being rotatably seated in bearings 84, 85 secured, as by welding, to the upper cross bar 64 and having worms 86, 8! engagin the worm gears 16, 11, whereby rotation of the cross shaft, 83, as by an end wheel 88 keyed thereto and having spaced openings to receive a handle 89, causes rotation of the rods and moves the cross bar H and the punch support vertically for fine punch adjustment to the work; the extent of the adjusting movement is indicated by a micrometer wheel 90 which is secured to the end wheel 88 and turns past a fixed pointer 9| secured to the cross bar 64. The ends 92 of the cross bar H are preferably split, so that thread wear can be taken up by tightening the bolts 93; the bolts 93 may be slightly loosened when the micrometer positioning adjustment is made. A stroke counter 94 is mounted on the vertical bearing support 10 and is actuated by a spring pull rod 95 secured to the cross bar i I.

The operation of the novel punch press is now clear. The stock is intermittently fed over the bed plate by the stock feed device, and the power is transmitted from the motor through the pulleys and the fly Wheel to the power shaft, the end of the power shaft having an eccentric pin which is set to obtain a stroke of fixed length,

' such as /2", /3", and l for example, the

setting being made so that the "power thrust is 4 always against the setting block, which is securely locked in the end of the power shaft. The eccentric pin, through its slide block connection, reciprocates the upper cross bars, and through the threaded rods reciprocates the lower cross bar which carries the punch housing and the punch. The spaced bearings for the threaded rods impart great strength and rigidity to the punch mechanism, and minimize wear, which may be taken up at the split bearings by use of shims, and the punch may be finely adjusted and positioned to the work without interruption of the punching operation by turning the threaded rods to relatively raise or lower the lower cross rod and thus obtain a fine positioning adjustment to the work.

'While I have described a specific constructional embodiment of my invention, it is obvious that changes in the size, shape, and arrangement of the parts, and in their operation and adjustment, may be made to suit different punch and stamping requirements, without departing from the spirit and the scope of the invention as defined in the appended claims.

Iclaim:

1. In a machine of the type described, a support including spaced vertical bearings, a power shaft, an eccentric pin on said power shaft, a punch cross bar, punch means on said punch cross bar, means associated with said spaced vertical bearings for guiding the punch cross bar, said means including spaced rods each having a threaded connection with said punch cross bar, means operatively connecting the eccentric pin to the punch cross bar for reciprocating the punch cross bar upon rotary movement of said eccentric pin including a slide block actuated by the eccentric pin and cross bar mechanism within which said slide block is slidably mounted, the cross bar mechanism being secured to the spaced rods, and means for adjusting the punch position of the punch means with respect to the eccentric pin, comprising a gear on each spaced rod, rotatable to thread the spaced rods in and out of the punch cross bar, and a manually actuated device for simultaneously rotating said gears.

2. In a machine of the type described, a support including spaced vertical bearings, a power shaft, an eccentric pin on said power shaft, a punch cross bar, punch means on said punch cross bar, means associated with said spaced vertical bearings for guiding the punch cross bar, said means including spaced rods each having a threaded connection with said punch cross bar, means operatively connecting the eccentric pin to the punch cross bar for reciprocating the punch cross bar upon rotary movement of said eccentric pin including a slide block actuated by the eccentric pin and cross bar mechanism within which said slide block is slidably mounted, the cross bar mechanism being secured to the spaced rods, and means for adjusting the punch position of the punch means with respect to the eccentric pin, comprising a worm gear on each spaced rod, rotatable to thread the spaced rods in and out of the punch cross bar, and a manually actuated worm for simultaneously rotating said gears.

3. In a machine of the type described, a support including spaced vertical bearings, a power shaft, an eccentric pin on said power shaft, punch cross bar mechanism guided for reciprocating movement in said spaced vertical bearings,

punch means mounted on said punch cross bar mechanism, means operatively connecting the eccentric pin to the punch cross bar mechanism for converting rotary motion of the eccentric pin to reciprocating movement of the punch means, and means for altering the punch position of the punch means with respect to the eccentric pin including a rotatable'worm gear device and a manually operable worm for rotating said device.

CARL G. PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 242,100 Barnes May 31, 1881 Number Number 

